Conventionally, gasoline delivery pipes for supplying gasoline to a plurality of cylinders of an engine provided with a plurality of injectors are known. Such gasoline delivery pipes sequentially jet out fuel, which is supplied via underfloor piping from a gasoline tank, through the plurality of injectors into the plurality of cylinders or intake pipes of the engine to mix the fuel with air and, by burning the air-fuel mixture, generate an output of the engine.
Return-less type gasoline delivery pipes, among these delivery pipes for gasoline, do not have piping for returning excess fuel to the fuel tank. For this reason, sudden pressure reductions when the internal pressure of the gasoline delivery pipe is reduced by fuel injection from an injector to an intake pipe or a cylinder of the engine, together with pressure waves that arise due to stopping the fuel injection, generate a pressure pulsation in the inside of the gasoline delivery pipe. The pressure pulsation is propagated to the vehicle as noise, which gives an unpleasant feeling to the driver and passengers. To reduce the pressure pulsation as described above, it has been proposed to provide delivery pipes with a pressure pulsation absorbing function by configuring the wall surfaces in flat shape. In gasoline delivery pipes having this pressure pulsation absorbing function, flexible absorber faces are formed in the outer wall, such that the pressure pulsation is absorbed and reduced by bending deformation of the absorber faces under the influence of the pressure generated in association with the fuel injection, thus enabling the generation of abnormal sound due to vibration to be prevented.
Now, in a case where an inlet pipe was connected, as shown in FIGS. 6 and 7, to a wall face of the delivery pipe main body 31 of a gasoline delivery pipe capable of reducing pulsation as described above, the bending deformation of wide walls 33, 34 and narrow walls 35, 36 of the delivery pipe main body 31 lead to stress being concentrated in the vicinity of the connecting portion 38 of a narrow wall 35 with the inlet pipe 32, such that there was a possibility of delivery pipe main body 31 being damaged. For preventing such damage, the method of connecting, as shown in FIG. 9, the inlet pipe 45 to an end cap 42 provided on either end of the delivery pipe main body 41, the method of connecting, as shown in FIG. 10 and patent document 1, the inlet pipe 55 to a portion near an end cap 51, and similar methods of connecting the inlet pipe 32, 45, 55 to a portion of the delivery pipe main body 31, 41, 51 where the bending deformation of the wide walls 33, 34, 43, 53 and narrow walls 35, 36, 44, 54 is less likely to occur are known.    Patent document 1: JP H4 252859 A